Device for drawing circles



June 26, 1923. 1,466,093

N. B. COSTOVICI DEVICE FOR DRAWING CIRCLES Filed Aug. 28, 1920 I: 2 s 4 5 s 7 a 10 IlllllllhmllllIIIIIIIIHIIIIIIHHIHHlllllililklllllhllllflHllillllllll imluu Patented June 26, 1923.

sr'rs NICOLAS BASILE COSTOVICI, OF LAUSANNE, SWITZERLAND, ASSIGNOR TO AIMERIGAN I NICOVICI DRAWING- INSTRUMENTS CORPORATION, OF NEW YORK, N. 1., A COM- PANY OF DELAWARE.

DEVICEFOR DRAVJING CIRCLES.

Application filed August 28, 1920. Serial No. 406,616.

To all whom it may concern):

Be it known that I, NICOLAS BASILE Cosrovror, a subject ofliumania, and residing at Lausanne, Rue du Grand-Chene 5, Switzerland, have invented certain new and useful Improvements in Devices for Drawing Circles, of which the following is a specification.

The subject-matter of this invention is a device for drawing circles comprising a center pin consisting of two parts rotatably inserted one into the other, whereof the one to be placed on the drawing paperorthe like is arranged at the one end of a bar that is to be held fast when circles-arebeing drawn, and the other is connected. with'the drawing instrument that is movable round the center pin. 1

The invention is illustrated by way of example in the accompanying drawing, wherein:

Fig. 1 is a perspective View of one form of drawing instrument according to the invention, and

Figs. 2 and 3 are elevations showing details on an enlarged scale.

7 throughout the several views.

Referring to the drawing, at the one end of the Hat graduated bar 1 is arranged at right-angles thereto a downwardly directed portion 2 having a foot a rotatable about a vertical pivot-pin 8, to enable the instrument to be conveniently placed on a horizontal sheet of drawing paper when the foot is placed at right-angles to the bar, as shown in Fig, 1, without danger of the bar tilting over on to its support. The bar 1, which can be used as a straight edge and as a square, carries at its other end in a screw-threaded hole 5, the lower part 6 of a two-part center pin 6, 7 The part 6 has a longitudinal bore 8 containing at the bottom a helical spring 9 whereon bears a pin 10 that is firmly carried by the upper part 7 and rotatably fits in the bore 8.

The part 7 is formed as a loop, into which is inserted the one end of a straight-edge 12 having a scale 11. Movable along this straight-edge or ruler 12 is a slide 13 which may carry a drawing-pen 14 or a drawingpencil 15 as in the well known compasses. The slide 13 is provided on the side op posite to its set-screw 16 with a window 17 and an index 18 for accurately setting the drawing-pen or pencil.

In order to be able to draw quite small. circles thehead of the slide 13, into which the pen or pencil fitting is inserted, is pivotally connected with the body of the slide, so that the point of the pencil or pen can be placed quite close to the pointof the center pin 6, 7, In order that the point of the pen oil or pen placed a little higher than the point of the center pin can be brought into contact with the drawing paper, pressure is brought to bear on the part 7 against the ac tion of the spring 9.

For the purpose of drawing circles the pencil or pen can be moved aroundthe center pin by means of a grip 19. Thishas at longitudinal aXis the straight-edge 1:2 with the pencil or pen can be moved about the center pin. This mode of turning the instrument will be used for drawing small and very small circles, whilst for drawing larger circles the grip 19 will preferably be placed on an upstanding pin 22 provided pin 22 is cylindrical on the slide 13. This and fits rotatably in the hole 20, so that the grip 19 is rotatable on the pin The grip 19 is hollow for holding spare pieces of lead and is closed at its upper end by a screw plug 23. When drawing larger circles, after the grip 19 has been placed on the pin 22 the one hand guides it round the center pin, whilst the lower part of the latter is held fast by means of the bar 1 with the other hand. The point of the center pin is pressed only gently into the drawing paper and does not rotate whilst circles are being drawn, however many circles may be drawn about the same center, so that no noticeable hole impairingthe appearance of the drawing is ever formed in the paper or other material on which the drawing is made, which is of considerable advantage in many cases.

The free end of the straight-edge 12 has a hole for the insertion of a lengthening piece 2 1 in order to draw larger circles than with the member 12 above. Instead of the latter a compass with drawing pen or pencil fitting could be employed as a device for drawing circles, whereofthe second limb musthave, however, instead of the usual center point the upper part 7, 10 of the above described center pin in order to obviate the formation of a hole in the paper:

I claim: a 1. In a device for drawing circles, the combination with a bar,of a center pin comprising two parts rotatable one relatively to the other about an axis common to the two, and whereof one part is mounted on said bar, an arm carrying the other part, and a marker carried by said arm.

2. In a device for drawing circles, the combination with a horizontal bar, of a twopart center pin whereof one part having a point at its lower end ismounted vertically insaid bar and has a vertical hole in its upper end, anda horizontal arnicarrying a vertical marker,the other part of said center pin being fast on said arm and having a pin rotatable insaid hole. a 3. In a device for drawing circles, the combination with a bar, of a center pin com prising two parts whereof one is fast on said bar, an arm, and a marker carried by the latter, the other part of said center pin having a loop mounted on said arm, and being swivelled to rotate about the longitudinal axis, of said former part. p 7

4:. In a device for drawing circles, the combination with a bar having a foot at one end, of a center pin comprising two parts whereof one is fast on the other endof said bar, an arm, and a marker slidable along said arm, the other part of said center pin being fast on one end ofsaid arm and arpart center pin whereof one part is fast on said bar and has a hole in its 113 381 end an arm, a marker slidable along said arm, the

other part of said center pin being mounted on said arm and having at one'side thereof a pivot rotatable in said hole, and at the other side thereof a. pin of angular cross-section,

and a grip detachably mounted on the latter pin for rotating said arm. 7 r v ,6. A device for drawing circles comprising the combination of a set-square having a longer horizontal limb and a shorter vertical limb, a foot pivoted on the bottom of said vertical limb, a two-part center pin whereof one part is mounted on the endof said hor zontal limb remote from said vertical limb, an arm, a marker slidable along said arm and having an upstanding pivot pin, the other part ofsaid center pin being mounted on said arm and having an upstanding pin of angularcross-section, and a grip detachably carried by the latter pin andadapted to take over said pivot pin. I

7. A device as specified in claim 2, in which a spring is located in thevertical hole forming a yielding support for the pin rotatable in said hole. p v

In testimony whereof I have afiixed my signature in presence of two witnesses.

N. B. COSTOVIGI.

Witnesses I F. MAROUARR, N. Cosrnronr. 

